Troj/Dropper-AK is a downloader Trojan which also drops and loads a helper component.
When run the Trojan will attempt to download a component from a remote website, copy itself to the Windows folder as FVProtect.exe and drop userconfig9x.dll also into the Windows folder.
Troj/Dropper-AK will then attempt to load the dll.
Sophos detects the downloaded component as Troj/Surila-O and the dropped dll as W32/Netsky-P.